Randomised crossover trial comparing algorithms and averaging times for automatic oxygen control in preterm infants

2021 ◽  
pp. fetalneonatal-2021-322096
Author(s):  
Christoph E Schwarz ◽  
Karen B Kreutzer ◽  
Lukas Langanky ◽  
Nicole S Wolf ◽  
Wolfgang Braun ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Random Order ◽  
Target Range ◽  
Oxygen Control ◽  
Non Invasive ◽  
Fraction Of Inspired Oxygen ◽  
Averaging Time ◽  
Randomised Controlled ◽  
Gestational Age At Birth

ObjectiveAutomatic control (SPOC) of the fraction of inspired oxygen (FiO2), based on continuous analysis of pulse oximeter saturation (SpO2), improves the proportion of time preterm infants spend within a specified SpO2-target range (Target%). We evaluated if a revised SPOC algorithm (SPOCnew, including an upper limit for FiO2) compared to both routine manual control (RMC) and the previously tested algorithm (SPOCold, unrestricted maximum FiO2) increases Target%, and evaluated the effect of the pulse oximeter’s averaging time on controlling the SpO2 signal during SPOC periods.DesignUnblinded, randomised controlled crossover study comparing 2 SPOC algorithms and 2 SpO2 averaging times in random order: 12 hours SPOCnew and 12 hours SPOCold (averaging time 2 s or 8 s for 6 hours each) were compared with 6-hour RMC. A generated list of random numbers was used for allocation sequence.SettingUniversity-affiliated tertiary neonatal intensive care unit, GermanyPatientsTwenty-four infants on non-invasive respiratory support with FiO2 >0.21 were analysed (median gestational age at birth, birth weight and age at randomisation were 25.3 weeks, 585 g and 30 days).Main outcome measureTarget%.ResultsMean (SD) [95% CI] Target% was 56% (9) [52, 59] for RMC versus 69% (9) [65, 72] for SPOCold_2s, 70% (7) [67, 73] for SPOCnew_2s, 71% (8) [68, 74] for SPOCold_8s and 72% (8) [69, 75] for SPOCnew_8s.ConclusionsIrrespective of SpO2-averaging time, Target% was higher with both SPOC algorithms compared to RMC. Despite limiting the maximum FiO2, SPOCnew remained significantly better at maintaining SpO2 within target range compared to RMC.Trial registrationNCT03785899

Automated control of oxygen titration in preterm infants on non-invasive respiratory support

2021 ◽  
pp. fetalneonatal-2020-321538
Author(s):  
Peter A Dargaville ◽  
Andrew P Marshall ◽  
Oliver J Ladlow ◽  
Charlotte Bannink ◽  
Rohan Jayakar ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Supplemental Oxygen ◽  
Respiratory Support ◽  
Target Range ◽  
Manual Control ◽  
Oxygen Control ◽  
Automated Control ◽  
Non Invasive ◽  
Automated Oxygen Control

ObjectiveTo evaluate the performance of a rapidly responsive adaptive algorithm (VDL1.1) for automated oxygen control in preterm infants with respiratory insufficiency.DesignInterventional cross-over study of a 24-hour period of automated oxygen control compared with aggregated data from two flanking periods of manual control (12 hours each).SettingNeonatal intensive care unit.ParticipantsPreterm infants receiving non-invasive respiratory support and supplemental oxygen; median birth gestation 27 weeks (IQR 26–28) and postnatal age 17 (12–23) days.InterventionAutomated oxygen titration with the VDL1.1 algorithm, with the incoming SpO2 signal derived from a standard oximetry probe, and the computed inspired oxygen concentration (FiO2) adjustments actuated by a motorised blender. The desired SpO2 range was 90%–94%, with bedside clinicians able to make corrective manual FiO2 adjustments at all times.Main outcome measuresTarget range (TR) time (SpO2 90%–94% or 90%–100% if in air), periods of SpO2 deviation, number of manual FiO2 adjustments and oxygen requirement were compared between automated and manual control periods.ResultsIn 60 cross-over studies in 35 infants, automated oxygen titration resulted in greater TR time (manual 58 (51–64)% vs automated 81 (72–85)%, p<0.001), less time at both extremes of oxygenation and considerably fewer prolonged hypoxaemic and hyperoxaemic episodes. The algorithm functioned effectively in every infant. Manual FiO2 adjustments were infrequent during automated control (0.11 adjustments/hour), and oxygen requirements were similar (manual 28 (25–32)% and automated 26 (24–32)%, p=0.13).ConclusionThe VDL1.1 algorithm was safe and effective in SpO2 targeting in preterm infants on non-invasive respiratory support.Trial registration numberACTRN12616000300471.

Randomised cross-over study of automated oxygen control for preterm infants receiving nasal high flow

2018 ◽  
pp. fetalneonatal-2018-315342 ◽  
Author(s):  
Peter R Reynolds ◽  
Thomas L Miller ◽  
Leonithas I Volakis ◽  
Nicky Holland ◽  
George C Dungan ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Primary Outcome Measure ◽  
High Flow ◽  
Target Range ◽  
Manual Control ◽  
Oxygen Control ◽  
Automated Control ◽  
Registration Number ◽  
Preterm Babies

ObjectiveTo evaluate a prototype automated controller (IntellO2) of the inspired fraction of oxygen (FiO2) in maintaining a target range of oxygen saturation (SpO2) in preterm babies receiving nasal high flow (HF) via the Vapotherm Precision Flow.DesignProspective two-centre order-randomised cross-over study.SettingNeonatal intensive care units.PatientsPreterm infants receiving HF with FiO2 ≥25%.InterventionAutomated versus manual control of FiO2 to maintain a target SpO2 range of 90%–95% (or 90%–100% if FiO2=21%).Main outcome measuresThe primary outcome measure was per cent of time spent within target SpO2 range. Secondary outcomes included the overall proportion and durations of SpO2 within specified hyperoxic and hypoxic ranges and the number of in-range episodes per hour.ResultsData were analysed from 30 preterm infants with median (IQR) gestation at birth of 26 (24–27) weeks, study age of 29 (18–53) days and study weight 1080 (959–1443) g. The target SpO2 range was achieved 80% of the time on automated (IntellO2) control (IQR 70%–87%) compared with 49% under manual control (IQR 40%–57%; p<0.0001). There were fewer episodes of SpO2 below 80% lasting at least 60 s under automated control (0 (IQR 0–1.25)) compared with manual control (5 (IQR 2.75–14)). There were no differences in the number of episodes per hour of SpO2 above 98% (4.5 (IQR 1.8–8.5) vs 5.5 (IQR 1.9–14); p=0.572) between the study arms.ConclusionsThe IntellO2 automated oxygen controller maintained patients in the target SpO2 range significantly better than manual adjustments in preterm babies receiving HF.Trial registration numberNCT02074774.

scholarly journals Designing a Remote Closed-Loop Automatic Oxygen Control in Preterm Infants

2020 ◽  
Vol 30 (4) ◽  
Author(s):  
Mohammad Reza Moradi ◽  
Sharareh R. Niakan Kalhori ◽  
Marian Ghazi Saeedi ◽  
Mohammad Reza Zarkesh ◽  
Abbas Habibelahi ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Pulse Oximeter ◽  
Closed Loop ◽  
Arterial Oxygen Saturation ◽  
Arterial Oxygen ◽  
Target Range ◽  
Preterm Neonates ◽  
Oxygen Control ◽  
Fraction Of Inspired Oxygen ◽  
To Receive

Background: Different automated systems have been developed to improve the maintenance of target range of arterial oxygen saturation (SPO2) in premature infants with respiratory distress. Objectives: This study aimed to develop a remote closed-loop automatic oxygen control (RCLAC) as an efficient monitoring device. Then the means of the fraction of inspired oxygen (FIO2) and SPO2 by routine manual control (RMC) and RCLAC were compared. Methods: A developmental-descriptive study was carried out in an Iranian hospital (Tehran, Iran; 2015 - 2017). Twenty-two preterm infants with gestational age 24 - 28 weeks entered the study. A database was prepared based on pulse oximeter parameters. A Wi-Fi module was implemented to receive data from a pulse oximeter and send inputs to the user’s mobile. Vibrate alarm was implemented for high or low FIO2. After receiving notifications associated with an increase or decrease of FIO2 levels and user’s confirmation; the alterations were applied on the ventilator. Results: The mean FIO2 in the RMC system was significantly higher than the RCLAC system (98.1 ± 2.67 vs 79.5 ± 16.03; P = 0.0001). According to the results, when the SPO2 reached close to target SPO2 range and consequently FIO2 changed (decreased or increased based on target SPO2), heart rate showed a regular beating with a decrease in the numbers. Conclusions: Remote closed-loop automatic oxygen control system as a simple device could prevent preterm neonates from sustained hypo-hyperoxemic and arrhythmia episodes. Moreover, by using RCLAC, there was no need for continuous monitoring that may reduce the workload of NICU medical staff. Collecting reliable data and recording information in digital forms were also other benefits. Further studies with larger sample size are strongly suggested.

Comparison of volume guarantee and volume-controlled ventilation both using closed loop inspired oxygen in preterm infants: a randomised crossover study (CLIO-VG study)

2021 ◽  
pp. fetalneonatal-2021-321712
Author(s):  
Vrinda Nair ◽  
Mithilesh Kumar Lal ◽  
Jenna Gillone ◽  
Prakash Kannan Loganathan ◽  
Thomas Edward Bachman
Keyword(s):  
Crossover Study ◽  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Primary Outcome ◽  
Target Range ◽  
Oxygen Control ◽  
Controlled Ventilation ◽  
Volume Controlled Ventilation ◽  
Significant Difference ◽  
Volume Controlled

ObjectiveThe objective of this study was to compare two different modes of ventilation in maintaining oxygen saturation (SpO2) in target range (90%–95%) in ventilated preterm infants cared for with automatic control of oxygen delivery (A-FiO2).DesignA single-centre randomised crossover study.SettingsA level III neonatal intensive care unit.PatientsPreterm infants receiving mechanical ventilation and oxygen requirement >21%.InterventionsVolume guarantee (VG) vs volume controlled ventilation (VCV) modes with automatic oxygen control (A-FiO2).OutcomesThe primary outcome of this study was the proportion of time spent with oxygen saturations in the target range (90%–95%) .ResultsNineteen preterm infants with a median gestation age 25 weeks (IQR: 24–28) and birth weight 685 g (IQR: 595–980) were enrolled in the study. There was no significant difference in primary outcome of median proportion of time spent in target saturation between the two arms (72% (57–81) in VG vs 75% (58–83) in VCV; p=0.98). There was no significant difference in the secondary outcomes of time spent in SpO2 <80% (0.03% vs 0.14%; p=0.51), time spent in SpO2 >98% (0.50% vs 0.08%; p=0.54), the median FiO2 (31% vs 29%; p=0.51) or manual adjustments carried out between VG and VCV, respectively. The number of episodes of prolonged hypoxaemia and hyperoxaemia were similar in the two groups.ConclusionThere was no significant difference in time spent in target SpO2 range between VG and VCV when A-FiO2 was used as the FiO2 controller in this crossover randomised control study.Trial registration numberNCT03865069.

Remote Closed-Loop Automatic Oxygen Control in Preterm Infants

2019 ◽  
Author(s):  
Mohammad Reza Moradi ◽  
Sharareh R. Niakan Kalhori ◽  
Marian Ghazi Saeedi ◽  
Mohammad Reza Zarkesh ◽  
Abbas Habibelahi ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Pulse Oximeter ◽  
Closed Loop ◽  
Arterial Oxygen Saturation ◽  
Arterial Oxygen ◽  
Target Range ◽  
Preterm Neonates ◽  
Oxygen Control ◽  
The Mean ◽  
Fraction Of Inspired Oxygen

Abstract Background Different automated systems have been developed to improve maintenance of target range of arterial oxygen saturation (SPO2) in premature infants with respiratory distress. This study aimed to develop a Remote Closed-Loop Automatic Oxygen Control (RCLAC) as an efficient monitoring device. Then the mean of fraction of inspired oxygen (FIO2) and SPO2 by routine manual control (RMC) and RCLAC were compared.Methods A developmental-descriptive study was carried out in an Iranian hospital (Tehran-Iran; 2015-2017). Eighteen preterm infants with gestational age 24-28 weeks entered the study. A database was prepared based on pulse oximeter parameters. A Wi-Fi module was implemented to receive data from pulse oximeter and send inputs to user's mobile. Vibrate alarm was implemented for high or low FIO2. After receiving notifications associated with increase or decrease of FIO2 levels and user's confirmation; the alterations were applied on the ventilator.Results The mean FIO2 in RMC system was significantly higher than RCLAC system (98.1± 2.67 vs. 79.5±16.03; p = 0.0001). According to the results, when the SPO2 reached close to target SPO2 range and consequently FIO2 changed (decreased or increased based on target SPO2), heart rate showed a regular beating with decrease in the numbers.Conclusion Remote Closed-Loop Automatic Oxygen Control system as a simple device could prevent preterm neonates from sustained hypo-hyperoxemic and arrhythmia episodes. Moreover by using RCLAC, there was no need for continuous monitoring that may reduce workload of NICUs medical staff. Collecting reliable data and recording information in digital forms were also other benefits.

Effectiveness of hydrocolloid nasal dressing pads in preventing nasal ulceration in preterm infants using non-invasive ventilation

MedPharmRes ◽  
2021 ◽  
Vol 5 (4) ◽  
pp. 46-51
Author(s):  
Chau Vu Bao Nguyen ◽  
Tinh Thu Nguyen ◽  
Tam Thi Thanh Pham ◽  
Sen Thi Hong Lam ◽  
Le An Pham ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Nasal Cannula ◽  
The Other ◽  
Control Group ◽  
Invasive Ventilation ◽  
Nasal Bridge ◽  
Non Invasive ◽  
Hydrocolloid Dressing ◽  
Non Invasive Ventilation

Background: The use of non-invasive ventilation (NIV) in preterm infants is becoming increasingly common. The use of cannula in NIV can cause ulceration of the nasal bridge with the current practices using the thin foam patches. This study aims to evaluate the effectiveness of hydrocolloid nasal dressing pads in preventing nasal ulceration comparing to that of the thin foam patches. Methods: A prospective cohort study using hydrocolloid dressing pads (1 November to 30 April 2020) was compared to that of a historical control group using thin foam dressing (1 April to 15 October 2019) to evaluate the effectiveness of hydrocolloid dressing pads. All participants were preterm infants (less than 37 weeks of gestational age) and used nasal cannula NIV at the Department of Neonatal Intensive Care (NICU), Children's Hospital 1. Results: 71 infants used hydrocolloid dressing pads, and 42 used ordinary thin foam nasal dressings. In the hydrocolloid dressings group, two infants (2.8%) had nasal ulcers; among them, one was mild, and the other was moderate. In comparison, ten infants (23.8%) using thin foam dressings developed ulcers, of which seven were mild, two were moderate, and one was severe. Using hydrocolloid nasal dressings significantly reduced nasal ulceration compared to thin foam dressings (OR = 0.09, 95%CI = 0.02 – 0.45). Conclusion: Using hydrocolloid nasal dressings for preterm infants on nasal cannula NIV significantly reduced nasal ulceration compared to ordinary thin foam dressings.

scholarly journals Longitudinal Study of music Therapy’s Effectiveness for Premature infants and their caregivers (LongSTEP): protocol for an international randomised trial

BMJ Open ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. e025062 ◽  
Author(s):  
Claire Ghetti ◽  
Łucja Bieleninik ◽  
Mari Hysing ◽  
Ingrid Kvestad ◽  
Jörg Assmus ◽  
...  
Keyword(s):  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Infant Development ◽  
Controlled Trial ◽  
Randomised Trial ◽  
Developmentally Appropriate ◽  
Well Being ◽  
Positive Effects ◽  
Implementation And Dissemination ◽  
Randomised Controlled

IntroductionPreterm birth has major medical, psychological and socioeconomic consequences worldwide. Music therapy (MT) has positive effects on physiological measures of preterm infants and maternal anxiety, but rigorous studies including long-term follow-up are missing. Drawing on caregivers’ inherent resources, this study emphasises caregiver involvement in MT to promote attuned, developmentally appropriate musical interactions that may be of mutual benefit to infant and parent. This study will determine whether MT, as delivered by a qualified music therapist during neonatal intensive care unit (NICU) hospitalisation and/or in home/municipal settings following discharge, is superior to standard care in improving bonding between primary caregivers and preterm infants, parent well-being and infant development.Methods and analysisDesign:international multicentre, assessor-blind, 2×2 factorial, pragmatic randomised controlled trial; informed by a completed feasibility study.Participants:250 preterm infants and their parents.Intervention:MT focusing on parental singing specifically tailored to infant responses, will be delivered during NICU and/or during a postdischarge 6-month period.Primary outcome:changes in mother–infant bonding at 6-month corrected age (CA), as measured by the Postpartum Bonding Questionnaire.Secondary outcomes: mother–infant bonding at discharge and at 12-month CA; child development over 24 months; and parental depression, anxiety and stress, and infant rehospitalisation, all over 12 months.Ethics and disseminationThe Regional Committees for Medical and Health Research Ethics approved the study (2018/994/REK Nord, 03 July 2018). Service users were involved in development of the study and will be involved in implementation and dissemination. Dissemination of findings will apply to local, national and international levels.Trial registration numberNCT03564184

scholarly journals Regional ventilation characteristics during non-invasive respiratory support in preterm infants

2020 ◽  
pp. fetalneonatal-2020-320449
Author(s):  
Jessica Thomson ◽  
Christoph M Rüegger ◽  
Elizabeth J Perkins ◽  
Prue M Pereira-Fantini ◽  
Olivia Farrell ◽  
...  
Keyword(s):  
Oxygen Saturation ◽  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Repeated Measure ◽  
Regional Ventilation ◽  
Quiet Breathing ◽  
Impedance Tomography ◽  
Non Invasive ◽  
Ventilation Inhomogeneity ◽  
The Right

ObjectivesTo determine the regional ventilation characteristics during non-invasive ventilation (NIV) in stable preterm infants. The secondary aim was to explore the relationship between indicators of ventilation homogeneity and other clinical measures of respiratory status.DesignProspective observational study.SettingTwo tertiary neonatal intensive care units.PatientsForty stable preterm infants born <30 weeks of gestation receiving either continuous positive airway pressure (n=32) or high-flow nasal cannulae (n=8) at least 24 hours after extubation at time of study.InterventionsContinuous electrical impedance tomography imaging of regional ventilation during 60 min of quiet breathing on clinician-determined non-invasive settings.Main outcome measuresGravity-dependent and right–left centre of ventilation (CoV), percentage of whole lung tidal volume (VT) by lung region and percentage of lung unventilated were determined for 120 artefact-free breaths/infant (4770 breaths included). Oxygen saturation, heart and respiratory rates were also measured.ResultsVentilation was greater in the right lung (mean 69.1 (SD 14.9)%) total VT and the gravity-non-dependent (ND) lung; ideal–actual CoV 1.4 (4.5)%. The central third of the lung received the most VT, followed by the non-dependent and dependent regions (p<0.0001 repeated-measure analysis of variance). Ventilation inhomogeneity was associated with worse peripheral capillary oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) (p=0.031, r2 0.12; linear regression). In those infants that later developed bronchopulmonary dysplasia (n=25), SpO2/FiO2 was worse and non-dependent ventilation inhomogeneity was greater than in those that did not (both p<0.05, t-test Welch correction).ConclusionsThere is high breath-by-breath variability in regional ventilation patterns during NIV in preterm infants. Ventilation favoured the ND lung, with ventilation inhomogeneity associated with worse oxygenation.

Direct swallowing training and oral sensorimotor stimulation in preterm infants: a randomised controlled trial

2021 ◽  
pp. fetalneonatal-2021-321945
Author(s):  
Ju Sun Heo ◽  
Ee-Kyung Kim ◽  
Sae Yun Kim ◽  
In Gyu Song ◽  
Young Mi Yoon ◽  
...  
Keyword(s):  
Randomised Controlled Trial ◽  
Preterm Infants ◽  
Neonatal Intensive Care ◽  
Controlled Trial ◽  
Tube Feeding ◽  
Tertiary Hospital ◽  
Oral Feeding ◽  
Very Preterm Infants ◽  
Very Preterm ◽  
Randomised Controlled

ObjectiveTo evaluate the effects of direct swallowing training (DST) alone and combined with oral sensorimotor stimulation (OSMS) on oral feeding ability in very preterm infants.DesignBlinded, parallel group, randomised controlled trial (1:1:1).SettingNeonatal intensive care unit of a South Korean tertiary hospital.ParticipantsPreterm infants born at <32 weeks of gestation who achieved full tube feeding.InterventionsTwo sessions per day were provided according to the randomly assigned groups (control: two times per day sham intervention; DST: DST and sham interventions, each once a day; DST+OSMS: DST and OSMS interventions, each once a day).Primary outcomeTime from start to independent oral feeding (IOF).ResultsAnalyses were conducted in 186 participants based on modified intention-to-treat (63 control; 63 DST; 60 DST+OSMS). The mean time from start to IOF differed significantly between the control, DST and DST+OSMS groups (21.1, 17.2 and 14.8 days, respectively, p=0.02). Compared with non-intervention, DST+OSMS significantly shortened the time from start to IOF (effect size: −0.49; 95% CI: −0.86 to –0.14; p=0.02), whereas DST did not. The proportion of feeding volume taken during the initial 5 min, an index of infants’ actual feeding ability when fatigue is minimal, increased earlier in the DST+OSMS than in the DST.ConclusionsIn very preterm infants, DST+OSMS led to the accelerated attainment of IOF compared with non-intervention, whereas DST alone did not. The effect of DST+OSMS on oral feeding ability appeared earlier than that of DST alone.Trial registration numberClinicalTrials.gov Registry (NCT02508571).

Continuous neurally adjusted ventilation: a feasibility study in preterm infants

2020 ◽  
Vol 105 (6) ◽  
pp. 640-645
Author(s):  
Marie-Eve Rochon ◽  
Gregory Lodygensky ◽  
Laurence Tabone ◽  
Sandrine Essouri ◽  
Sylvain Morneau ◽  
...  
Keyword(s):  
Electrical Activity ◽  
Preterm Infants ◽  
Feasibility Study ◽  
Neonatal Intensive Care ◽  
Positive Pressure ◽  
Non Invasive ◽  
Diaphragm Electrical Activity ◽  
Registration Number ◽  
Level 3 ◽  
The Impact

ObjectivesTo assess the feasibility and tolerance of NeuroPAP, a new non-invasive ventilation mode which continuously adjusts (during both inspiration and expiration) the pressure support proportionally to the diaphragm electrical activity (Edi), in preterm infants and to evaluate the impact on ventilation pressure and Edi.DesignProspective cross-over single-centre feasibility study.SettingOne level 3 neonatal intensive care unit in Canada.PatientsStable preterm infants ventilated with non-invasive positive pressure ventilation (NIPPV).InterventionsSubjects were successively ventilated in NIPPV with prestudy settings (30 min), in NeuroPAP with minimal pressure similar to NIPPV PEEP (positive end-expiratory pressure) (60 min), in NeuroPAP with minimal pressure reduced by 2 cmH20 (60 min), in continuous positive airway pressure (15 min) and again in NIPPV (30 min). Main outcome measures included tolerance, ventilation pressure, Edi and patient-ventilator synchrony.ResultsTwenty infants born at 28.0±1.0 weeks were included. NeuroPAP was well tolerated and could be delivered during 100% of planned period. During NeuroPAP, the PEEP was continuously adjusted proportionally to tonic diaphragm Edi, although the average PEEP value was similar to the set minimal pressure. During NeuroPAP, 83 (78–86)% breaths were well synchronised vs 9 (6–12)% breaths during NIPPV (p<0.001).ConclusionsNeuroPAP is feasible and well tolerated in stable preterm infants, and it allows transient adaptation in PEEP in response to tonic diaphragm electrical activity changes. Further studies are warranted to determine the impact of these findings on clinical outcomes.Trial registration numberNCT02480205.

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